A head up display emits light that reflects from the front windshield to be seen by the driver. The light appears to come from a virtual image in front of the driver and in front of the windshield.
Conventional head up displays create the virtual image by first using a display to create an image. Next, the light from the image is reflected from one or more mirrors, and then the light from the mirrors is reflected from the windshield. The mirrors are designed and positioned relative to the display so that the light seen by the driver, which is reflected from the windshield, appears to come from a virtual image that is outside of the vehicle. The mirrors and display are typically contained in a package that occupies a volume beneath the top surface of the dashboard.
Currently known vehicles include separate displays or image sources for the HUD and instrument cluster. Two separate displays are typically used to produce a cluster image and an HUD image.